Engine piston



1 ing expansion ring;

Fatented Sept. 12, 19122.

EMU. IVIULLEM, OF NORTH ARLINGTON,

ENGINE PISTQN.

Application filed April 30, 1920. Serial No. 377,738.

To all whom it may concern 7 Be it known that I, EMIL MULLERN, a citizen of Hungary, and a resident of North 'Arlington, in the county of Hudson and State of New Jersey, have invented certain new and useful Improvements in Engine Pistons, of which the followingis a full,

clear, and exact description.

Among the principal objects which the present invention has in view are: To avoid distortion of piston rings when disposing the same for service; to simplify the operation of cleaning and repairing piston heads; to avoid loss of compression; to prevent the upward passage of oil to lubricate the cylinder; and to prevent dis-arrangement or vibration of piston parts.

Bra/wings,

. Figure 1 is a side elevation, partly in section, of a piston constructed and arranged in accordance with the present invention;

Figure 2 is a top view of the piston; Figure 3 is a perspective view showing one of the packingrings with which the piston is provided; R

Figure 1 is a cross section of the top wip- Figure 5 is a detail View showing fragments of the same, and aportion of the lapped joint formed therein; I

Figure 6 is a detail view showing in plan a local washer employed in constructing the herein'disclosed piston; and a Figure 7 'is a side view of one'of the nuts.

Description. I

As seen in the drawings, pistons 12, when constructed in accordance with the present invention, have the usual apron provided with wrist pin bearings 13. Diflering from the usual construction, however, the .upper portion of the piston casting is reduced to form a bench 14, which extends around the piston to form a rest for the supporting rings 15,16 and 17. The rings 15, 16 and 17 are solid and are machined to fit snuglythev cylindrical wall 18 of the cap head 19.

l The head 19 has an overhanging flange 20,

the upper wall'of which is inwardly tapered. In service the flange 20 presses the rings 15,

' 16 and 17 firmly upon the bench 14.

The pressure thus applied to the rings 15, 16 and 17 isimparted by means of the cap nuts 21, which engage the stud bolts-'22 in the reduced portionof thepiston 12, as

' best seen in Figure 1 of the drawings. The

ton. The outer edges of the flanges 23 arein service covered by the head 19. The greater diameter of the flanges 23 serves as detents or retainers for the bolts 22, when frictionally engaged by the sockets provided.

for the said flanges or by the overhanging portion of the heads.

As seen. best in Figure 7 of the drawings, the-barrel 24 of each of the nuts 21 is tapered', and is furnished with an annular groove 25, which is provided to form with the lubricant present a seal to prevent the passage of gases through the joint between the said barrel and the openings formed in the head 19 therefor. The nuts 21 may be locked inservioe in any approved manner. It is preferred to use the fembrated washer 26, shown best in Figure 6 of the drawings. Each washer has forced outward from the side thereof a detent 27, to receive which the head 19 is provided with a series of sockets. When the nuts 21 are set up tight, one or other of the sections of the washer 26 are upturned against one of the faucets of the nut, to thereafter hold the same against rotation, the detents .27 each operating to holdthe washer 26 from rotation.

The rings 15, 16 and 17 are reduced to,

form benches for the reception of split expansion rings 28 and 29. The rings 28 are rectangular 'in cross section, and, as shown best in Figure? of the drawin s, are split,

the cross cuts 30 being dispos at an angle to the radii of the ring. These rings are constructed in the manner usually emplo ed for constructing piston rings, except t at,

ice-

conformity with the usual practice. When 1 the rings are stretched, as in accordance with the present practice, to ass over the piston to the grooves provide therein, the

' rings are drawn out of their natural seat and V are given an added tension, which causesthemto rub on the side wallstof the cylinder unevenly, resulting in many inout-changinglthe original seat, being slipped- ",easily andwithoutforce over the reduced portions of the supporting, rings and 16.

To remove or' replace the, ring 29, the ring 17 is removed in the same manner-as described with reference to therings 15 and 16, 1 and the ring 29 is removed from'the reduced portion of the'said ring 17, or replaced thereon without} distortion of the said rin -;When the supporting rings 15, 16 and- 1 and their associated split rings 28 and 29 are disposed in service, as shown bestin Figure 1, .they-are'held on the wall 18 by'a wire 'keeper 31. Yflhekeeper'31 is constructed'of Lspr'ing wire,' to contract upon a I groove formed adjacent the lower edgeofthe wall 18;- When the keeper is in position, it isob- 'vious that the various rings above enumjeratedcanhot berem'oved fromthe wall 18.

when the head 19 with its accompanying brings, is-lifted from the'pistons 12, after the I 4 removal of the nuts 21, the groove in which n the keeper 31 rests is exposechso that by J the insertionof any suitable tool the said- '35 and the various rings easily removed from.

keeper may be withdrawn from its groove the wall 18.

To lift the head 19 from the piston'12 after the nuts 21'h'ave-been removed,'-I' pro;

vide tapped bottomed holes 32, one ofwhich is shown in Figure 20f the drawings. In-

service' the washers 26 cover these holes, preventlng the admission of carbon or other foreign substance thereto.

As'shown best in Figure i of the drawings, the ring'29.-hasla.- rectangular body 33,

and chamfered extensions 34 and 35'. As

seen in Figure lof the' drawings, the chamfered GXtGIlSiOIIBhiS exposed to pressure which may b'eapplied tothe head of the piston. -In automobile engine service where a portion of the cycle is a compression stroke, thexcompression' operating upon the T inclined surface of the extension 34 expands '55 the ring 29 outwardly against the wall of r the engine cylinder. This effect is greatest at the moment when lgnltionoccurs with the result that at the moment of greatest expansion pressure the open packing ring with which the pistonis provided is forcefully expanded'to close the .joint between the 1ston and-the cylinder wall. 'Itrisv obvious that at theend ofthe I power stroke when the resultsimmediately in a diminution of the pressure of the ring 29 on the cylinder walls thus overcoming any tendency to drag on the cylinder during the operation of the piston between, the compression strokes. The extension 35 of. the ring 29 employedin the present invention for wiping the wall of the cylinder in the downward on power stroke thereof. The upper surface of the supporting ring 17 is cut away toform' an annular recess under and facing the tapered surface of the extension 35. The

recess thus formed constitutes a pocket into which the oil wiped from the surface of the cylinder by the extension 35 is placed, and thus prevented from being carried into the v 'the head 19 may be quickly and easily re- To give access to the keeper 31,]the lower i' sf'u rfz'iceofthe ring 15 is chamfered'as best f 4 seen in Figure 1 ofthe drawings, so that.

moved from the piston, without removing the piston from thecylinder. The head and returned to the pistons from which they.

have been removed with ease and without removing the pistons fromv their respective cylinders. v

-r As seen best in Fig.4: of the drawings, the ring 29 is preferably constructed of two half sections same being reversible. The halfsections are preferably pinned together and may be arranged so that the lapped end sections shown in Fig. 5 may difier 1n form or' be placed out of alignment.

Claims; i

1. An engine piston comprising a body having a cylindrical reduced end; a solid supporting ring removably mountedon said end,v said ring being recessed to form a groove for the reception of an expansible' packing ring; a packing ring having a beveled extension exposed to the compression chamber of the cylinder with. which said piston is associated for being expanded by the pressure formed insaid chamber, said ring havin a chambered extension at the opposite e ge thereof for wiping the wall of the cylinder with which said piston associated.

2. An engine piston comprisi a body having a cylindrical reduced en a solid V supporting ring removably mounted on said .end, said ring being recessed to form a groove for the reception of an expansible packin ring; a packin ring having a bevele extension expose tothe compreslee inseam sion chamber of the cylinder with which said piston is associated for being expanded by the pressure formed in said chamber, said ring having a chamfered extension at the opposite edge thereof for wiping the wall of the cylinder with which said piston is associated; and means associated with said supporting ring for gathering the material wiped from the wall of said cylinder.

3. An engine piston comprising a body having a reduced cylindrical end forming a ciated with .one of said supporting rings,

saidsplit rings being assembled on said sup porting rings without distension of said split rings; and means for rigidly connectingsaid head with the reduced end of said piston, said means embodying a series of stud bolts permanently mounted in said end, and nuts engaging said bolts, said nuts extending into perforations formed in said head and overhanging the same to force said head toward said end;

4. An engine piston comprising a body having a reduced cylindrical end forming a sup-porting bench; a cap head snugly fitting said end, and having an overhanging flange to form in conjunction with said bench an annular groove; a plurality of supporting rings removably fitted on said. head under said flange; a keeper mounted on said head for holding said supporting rings in service relation to said head; a plurality of split packing rings each resting upon and associated with one of said supporting rings, said split rings being assembled on said su porting rings without distension of said sp it rings; and means for rigidly connecting said head with the reduced end of said piston, said means embodying a series of stud bolts permanentlymounted in said end, and nuts engaging said bolts, said nuts extending into perforations formed in said headand overhanging the same to force said head toward said end, said nuts having each an extension tapered in correspondence with perfora- I tions formed in said head.

EMIL MULLERN. 

